I'm with Dr. Ken Flower, and Dr. Ken Flower,
a lecturer in agronomy at the University of Western Australia.
Ken, we've had a revolution in the Australian cropping scene in the last 20 or so years.
And that's been the introduction of no-tillage agriculture.
You've been at the forefront of no-till agriculture in Australia.
Can you tell us about this revolution that has occurred?
Thanks, Steve.
The revolution actually started before I got here.
I've been in Australia since 2004.
I was originally from Zimbabwe.
And when I came over I joined the Western Australian No-Tillage Farmers Association,
who really were one of the pioneers of no-till.
And it was started down on the south coast because they were getting severe wind erosion.
And farmers really had to do something to try and get over that issue.
And that's when they really got into no-till.
And not only did it reduce erosion but increase yields significantly.
So that's really why it took off.
So it was a huge revolution and I think now over 95% of farmers are using no-till.
So, two of the big advantages is reduction in erosion,
but you also mention increased yields.
Could you expand on those two big advantages of no-till?
Yeah, so no-till has significantly increased yield.
One of the key factors is timeliness of seeding.
If one is in a system where you're plowing,
then obviously you have to wait for the rains before you can actually put the plowing,
whereas with no-till you can just go straight in without
any tillage and using the herbicides essentially as a chemical plow.
So, timeliness of seeding,
being able to seed early has been a key factor.
And there's a yield decrease from seeding a little bit later.
And they say anything up to between 10 to 50 kilograms per hectare
per day that seeding is delayed beyond the optimum time.
So we're really getting advantages in being able to seed our crops
earlier than used to prevail when we plowed
the ground and we're also saving precious soil moisture too, aren't we?
Yes. So, Steve, when I first came here I
realized that moisture is the key driving our cropping system.
And talking to farmers,
they were measuring moisture in points which is like a quarter,
one point is a quarter of a millimeter and I realized then how precious that water was.
And yes, the water is absolutely crucial,
the main driver of our cropping system.
So what no-till has allowed is that farmers conserve the maximum amount of
water and that water then goes into crop growth and increased yield.
So it's the timeliness of seeding and
the additional soil moisture saved with the no-till system.
Right. Now those big advantages of course can't occur without
the necessary machinery for no-till agriculture.
Obviously when we're removing the plow we've
got to have a different system to plant the crop seed.
Yes, that's right. I mean No-till worldwide takes many different forms.
So some no-till farmers in other countries don't use in any tillage,
it would be hand cultivation and they are still
implementing a sort of a no-till conservation agriculture system.
But in our Western Australian system we have
large farms and use of machinery is essential.
So one of the things with machinery obviously is that it compacts soil.
So when we remove the tillage from the system that can
result in compaction if we're still driving over the fields with large machinery.
So one of the sort of complementary technologies
that goes along with no-till is controlled traffic.
So essentially that is restricting all the wheel tracks
to the same areas and never driving on other areas of the paddock.
That also encourages farmers to get
very wide machinery so that you're actually compacting minimal amounts of soil.
And so the no-tillage with
controlled traffic is a very complementary system, it fits well.
Right, so big farms, big wide machinery.
How about the actual seeding part of this with no-till,
how do we actually achieve putting a seed into the soil when we're not plowing soil?
So with our machinery what are we're doing
is we're just cutting a narrow slot into the soil,
at the correct seeding depth,
and then putting the seed in.
We do create a little bit of a furrow.
So there is two types of seeders.
One is called a tine seeder and the other one is a disc opener.
With a tine seeder,
it's like pulling a narrow knife, so it's called a knife point seeder,
or putting a narrow knife through the soil.
And that creates a furrow,
and the fertilizer is put down first and then the seed.
And then a press wheel comes along behind and that's really important because
it leaves a small little furrow in the crop row,
so any little bit of moisture that comes will actually run down that furrow.
A disc seeder is similar and disc seeder has
even less soil disturbance than the tine seeder.
So essentially we cut through the residue that we leave on
the soil surface and just place the seed
at the right depth with very little other soil disturbance.
So you mention we're leaving the crop residue from the previously harvested crop.
I think that's an important part of protecting the soil as well, is that so?
Yes, that's right. But the crop residue on the soil surface is seen as one of
the most important probably components of
zero tillage because with the crop residue there,
then when you get rain it doesn't run off and you get good infiltration,
and it also reduces evaporation of soil water,
so increasing the soil water and obviously erosion control.
So the amount of residue left on the soil surface is a key component,
and although sometimes you can do too much residue
and that makes it more difficult to seed into,
but keeping residue on the soil surface is a key component.
Right. And has there been any challenges that
have occurred that perhaps we're not foreseeing and are there
really any challenges to the ongoing success of no-till in Australian agriculture?
Steve, there are a number of challenges.
Probably one of the main ones is herbicide resistance or weed resistance to herbicides,
so because we've taken the tillage of the system
completely reliant on herbicides for weed control.
So potentially overuse of
herbicides could lead the weeds to become resistant to the herbicides.
So that is a major challenge and a significant amount of research going on about that.
And the other challenge is to do soil compaction.
Some of our soils will compact naturally even without machine really driving over it.
So farmers have found in some cases a yield response to some form of ripping for example,
to loosen that compaction,
and that can get a yield response.
So even though it's a no-till system, occasionally,
some form of tillage like ripping or something like that can basically
increase production levels back up to
the high level when farmers first went into no-till.
But on other soils that don't compact then they wouldn't need to do
any of that tillage or ripping.
I see. So in some of our soil in Australia,
an occasional soil plowing or conversion to remedy issues and then returning to
many years of no-till may be the most sensible economic and sustainable system.
Yes, that's the way it seems.
Initially I was thinking,
and the information we had was that you
shouldn't use any form tillage in a no-till system.
But if you have a serious problem with soil acidity or compaction,
then essentially your yields start to go down,
the amount of biomass or growth you get decreases.
And that essentially results in a decrease in
organic carbon going into the soil which has a negative impact.
So, that occasional tillage,
very occasional can actually remedy that problem,
you can put on lime and incorporate or loosen
that compaction and then go back to a no-till system and then your crop yields go up,
and the amount of biomass going back in the soil also goes up.
So that has a positive influence on the system.
Major field crops like wheat, et cetera,
95% are seeded with no-till or minimum till farming systems,
do you expect that to continue into the future?
Yes, absolutely.
I think without no-till our yields would go back,
they would start to decline.
Really because we have such short seasons and the rain can stop pretty quickly,
so we need to get that crop and on time.
And also we have a soil that is very prone to erosion.
So, no-till is absolutely key to maintaining that production
even though we might have to occasionally use some form of tillage to remedy issues.
